Route reliability record
CHS→ORD
Charleston to Chicago
- Flights
- 2,091
- Period
- July 2025 to June 2026
- Distance
- 760 mi
- Carriers
- 6
This route lands a B, about a point worse than the national rate of 77.6%. About one flight in four arrive 15 minutes late or worse, and those flights are late by a little over an hour on average. That is a workable record, not a spotless one. That rests on 2,091 flights, of which Envoy Air flew 562 at 80.1% on time.
Envoy Air is the most reliable of the three carriers covered here at 80.1% on time across 562 flights.
Key figures
On time
76.6%
Arrivals under 15 minutes late, of 2,022 completed flights
Avg delay
74 min
Across delayed arrivals only, not all flights
Cancelled
2.49%
National rate is 1.81%
Best carrier
Envoy
80.1% on time across 562 flights
These figures cover 2,091 flights between July 2025 and June 2026. Beyond the headline rate, 8.1% of arrivals land a full hour or more behind schedule. That is the number that wrecks a connection, and it is not visible in an on-time percentage alone.
Carrier by carrier
Which airline is most reliable on CHS to ORD
The choice of carrier is not cosmetic here. Envoy Air arrives on time 80.1% of the time; Republic Airways manages 70.5%. Sample sizes sit next to every figure, because a two-point gap across 456 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| PSA Airlinesthin sample | 1 | 100.0% | — | 0.00% | A+ |
| American Airlinesthin sample | 238 | 81.0% | 118 min | 1.68% | B |
| Envoy Air | 562 | 80.1% | 75 min | 2.67% | B |
| United Airlines | 749 | 77.1% | 73 min | 2.00% | B |
| Republic Airways | 456 | 70.5% | 52 min | 3.07% | C− |
| SkyWest Airlinesthin sample | 85 | 69.1% | 124 min | 4.71% | C− |
Republic Airways cancels 3.1% of what it schedules here, the highest in the table. A cancelled flight never appears in an on-time rate, so read that column alongside the punctuality one rather than after it.
Departure window
The best time of day to leave
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 25 points, against 10 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am487 flights86.1%
- 8am–11am157 flights86.0%
- 11am–2pm688 flights82.2%
- 2pm–5pm276 flights64.4%
- 5pm–8pm418 flights61.0%
- 8pm–5am65 flights72.9%
Scale runs 55% to 90%. Rows with fewer than 30 flights show a dash.
The 5pm–8pm window is where this operation falls apart: 61.0% on time, against 86.1% for the 5am–8am slot. By evening the aircraft flying these rotations have absorbed a full day of small delays and there is no slack left to recover in. The 11am–2pm window is the busiest, with 688 flights scheduled in it.
Across the year
When delays peak on this route
This route's year swings by 15 points from best month to worst, which is wide. An annual average tells you very little about the week you are actually flying, so read the strip rather than the headline if your dates are fixed.
July is the worst month at 68.7% on time, 15 points below August, the best at 83.5%. Summer afternoon convection and peak-season schedules land on the same weeks every year, so this is a pattern you can book around rather than a run of bad luck. March was the busiest month here, with 209 flights.
Across the week, Thursday is the strongest day at 80.7% on time and Sunday the weakest at 69.9%. 11 points is a smaller lever than departure hour, but it is free.
Delay causes
Why this route gets delayed
One category carries most of the weight here. National Airspace System accounts for 42% of the 35,000 delay minutes carriers reported, and the remaining four split what is left. The split is by minutes rather than by flights, so a few very long delays count for as much as many short ones.
- 42%National Airspace System
- 31%Late-arriving aircraft
- 24%Carrier
- 3%Extreme weather
- 0%Security
42% of delay minutes are charged to the National Airspace System: air traffic volume, runway configuration, ground stops. No carrier can price its way out of that, which is why airport choice moves the number here more than carrier choice does. That is 15,000 minutes out of 35,000, against a national NAS share of 21%. The split is drawn from 35,198 reported delay minutes.
The practical consequence: the 5am–8am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 86.1% on time here.
Cancellations sit at 2.49% against a national 1.81%, which is ordinary. Diversions add another 0.81%.
Connections and stage length
What a delay here actually costs
8.1% of arrivals land an hour or more late, close to the national 8.1%. That is the figure that decides a connection, and it says a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route are the a little over an hour kind, which a normal layover absorbs.
The 760 miles between these two airports put this in the middle of the US network, around two and a half to three hours of block time. That is enough cruise to absorb a ten-minute late pushback and not enough to absorb thirty. It is also long enough that the aircraft usually flies three or four legs a day rather than six, which slows how fast delay compounds.
The return leg runs 75.3% on time across 2,091 flights, within about a point of this direction. The two legs are scored separately because they usually differ; on this city pair they happen not to.
The sample behind these figures is 2,091 flights, enough that the headline rate is stable to within roughly a point. The hour-block and month splits divide that further, so read the thinner bars with more caution than the headline.
What to do with this
Booking this route
Put together: the calendar is the biggest lever here, not the carrier or the hour. August runs 83.5% on time and July 68.7%, a swing of 15 points. If the dates move at all, move them out of July before you think about anything else. 2,022 completed flights over 12 months sit behind that.
Common questions
CHS to ORD questions
How often is CHS to ORD delayed?
About one flight in four arrive at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 23.4% of the 2,091 flights in this analysis, against 22.4% nationally. Delayed flights are late by a little over an hour on average.
Which airline is most reliable on CHS to ORD?
Envoy Air leads at 80.1% on time across 562 flights. Republic Airways is at the other end on 70.5%, a gap of 10 points. Sample size matters as much as the percentage: a rate built from a few hundred flights moves around far more than one built from ten thousand.
What time of day has the fewest delays on CHS to ORD?
The 5am–8am departure window is the strongest at 86.1% on time. The 5pm–8pm window is the weakest at 61.0%, 25 points behind. Later departures inherit delays from earlier flights the same aircraft has already flown, which is why the curve slopes the way it does.
How bad are July delays on CHS to ORD?
July is the weakest month at 68.7% on time, compared with 83.5% in August. Across the year that is 15 points between the best and worst months. Moving flexible dates out of that month is one of the few things that reliably helps.
Related
Where to go next
- ORD to CHS — the return legseparate record
- Chicago O'Hare International (ORD) delay statistics
- PSA Airlines on-time record100.0%
- American Airlines on-time record81.0%
- Envoy Air on-time record80.1%
- The best time of day to fly, according to 7.04 million flight records
- Connecting flights: how much buffer the data says you need
Direction matters. CHS to ORD and ORD to CHS are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.
Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Updated monthly. How this data is collected.